[Acoustic analysis of certain consonants using a computed model of the peripheral auditory system]

Stop consonants [p], [t], [k] and a fricative [s] were acoustically analyzed using a computed model of the peripheral auditory system in 12 normal subjects and 12 patients with tumors of the tongue who had undergone surgical resection and reconstruction. The model is a combination of the cochlear model that consists of 28 FIR filters (Delgutte) and the inner hair-cell/auditory nerve synapse model (Meddis), with some modification. It simulates firing of the auditory nerve in every channel related to the FIR filters in response to an input voice signal. Phonetic characteristics of the tested consonants were more clearly visualized by observing firing patterns and voice onset time (VOT) using this auditory model than with use of the conventional soundspectrogram. In patients with tumors of the tongue, the degree of distorted articulation and the area of surgical resection were significantly related to obscurity of the phonetic characteristics of the stop consonants [t] and [k]. Acoustic analysis using this auditory model may serve as a useful tool for voice analysis in research and in the clinical field.